1. Field of the Invention
This invention relates to a method for brazing metal components for use in medical equipment, a metal assembly produced by the method and an endoscope provided with the metal assembly.
2. Description of the Prior Art
In medical equipment such as endoscopes, there is an apparatus of the type in which various instruments are to be inserted into the inside of a patient through the apparatus. Examples of such instruments include a monitoring scope which roles as a sensor for diagnosing the inside of a patient, a surgical knife for collecting a part of a body tissue, and an actuator for supplying a liquid for disinfecting or washing a part to be diagnosed or a gas such as air for locally blowing up the inside of a body cavity for making the diagnosis easy, and the like.
In general, such medical equipment is provided with a metal assembly so-called as a cylinder assembly through which various sensors and actuators are connected to tubes and wires and the like (see, for example, Japanese Laid-open Patent Application Publication No. 2003-199706).
In such a cylinder assembly, a cylinder body is brazed or joined with various pipe joints or the like which guide tubes and wires for connecting sensors and actuators which are to be placed inside the body cavity with operating sections used in the outside of the patient.
Conventionally, when the cylinder body is coupled with the pipe joints, openings are formed in the cylinder body, and then each pipe joint is inserted into the opening and then the joint portion is brazed together using various brazing filler metals.
In the meantime, recently, there are cases that resistant bacteria which cause hospital-in infection and deadly germs such as SARS are spread in hospitals. Therefore, there is a tendency that the medical equipment is disinfected or sterilized with a strong disinfectant containing peracetic acid and the like.
However, this in turn raises a problem in that the brazing portions (joint portions) in the conventional metal assemblies which were formed using various brazing filler metals are eroded with the strong disinfectant containing peracetic acid and the like, thus leading to a case that the function thereof is impaired.